‘Persistent armed fentanyl dealer’ in Seattle sentenced to 20 years in federal prison

Leon Henderson, 34, was arrested three times in 2023, according to a news release from the U.S. Attorney’s Office for the Western District of Washington. Across the arrests, investigators recovered more than 18,000 fentanyl pills, including about 10,000 pills during the final arrest.

In November 2025, a jury convicted him of three counts of possession of controlled substances with intent to distribute, two counts of possessing a firearm in furtherance of a drug trafficking crime, and two counts of unlawful possession of a firearm.

“Henderson’s crimes result in a mandatory minimum sentence of 20 years: 10 years for drug possession counts and a consecutive five years for each of the drug-related firearm counts,” the news release stated.

Federal authorities said the case highlights the ongoing danger of fentanyl distribution in vulnerable communities.

“Even though Mr. Henderson had multiple chances to change his destructive behavior, he persisted in selling fentanyl to homeless and vulnerable individuals while illegally in possession of stolen, loaded firearms,” W. Mike Herrington, special agent in charge of the FBI Seattle field office, stated. “Every time Mr. Henderson was arrested, he had even more fentanyl pills than the last, thousands on each occasion, showing he still has not learned his lesson even after repeated arrests.”

Judge: Seattle man’s drug dealing could have caused 18,000 overdoses

At the hearing, U.S. District Judge Jamal N. Whitehead noted that Henderson knew he was dealing to homeless addicts who would struggle to resist the temptation.

“The numbers in this case speak volumes,” Whitehead stated.

Henderson had over 18,000 fentanyl pills, 220 grams of fentanyl powder, and 700 grams of methamphetamine.

Selling the fentanyl pills for “a dollar per pill,” he could have caused “18,000 potential overdoses in our community,” Whitehead stated.

Prosecutors said Henderson was carrying loaded guns during two of the arrests.

“This case exemplifies the effort federal law enforcement is making around crime hotspots in our city, such as the North Aurora emphasis area,” First Assistant U.S. Attorney Neil Floyd stated. “The FBI and Seattle Police Department identified this area as one where federal attention could make a difference. This case took significant deadly drugs, firearms, and a habitual criminal off the street.”

Henderson’s first arrest in this case came on January 25, 2023, in North Seattle.

“Henderson was contacted at his car, parked outside the Park Plaza Motel on Aurora. He had $2,770 cash in his pocket,” the release stated. “When the car was searched, law enforcement found around 600 grams of methamphetamine, 1,700 fentanyl pills, 200 grams of fentanyl powder, and a loaded pistol under the driver’s seat. Henderson’s DNA was on the pistol and on a second gun found in a bag with narcotics.”

On May 5, police arrested him in Seattle’s Capitol Hill neighborhood. At that time, he had about 7,000 fentanyl pills, a firearm, and cash, authorities said.

“And finally, on September 13, 2023, Henderson was arrested in Ballard near a homeless encampment,” the release stated. “Henderson possessed a backpack with nearly 10,000 fentanyl pills.”

In 2019, he was convicted of promoting prostitution.

Authorities said Henderson forced the victim to be a sex worker, “injecting her with heroin and threatening her with death.”

In the drug case, authorities said he was arrested with a different female companion each time. In January, that person was allegedly involved in prostitution. The third time, the woman was reported as a missing person in Clallam County.

“At a minimum, this suggests that Mr. Henderson involved others in his drug trafficking activity,” the release stated. “At worst, he continued to promote prostitution alongside his drug trafficking business. Under either scenario, his illegal possession of guns endangered his female associates.”

After Henderson serves his prison time, he will be on supervised release for five years.

Frank Lenzi is the News Director for KIRO Newsradio. Read more of his stories here.